Provided is a storage controller and method of controlling same which, if part of a storage area of a local memory is used as cache memory, enable an access conflict for access to a parallel bus connected to the local memory to be avoided.A storage controller which exercises control of data between a host system and a storage apparatus, comprising a data transfer control unit which exercises control to transfer the data on the basis of a read/write request from the host system; a cache memory which is connected to the data transfer control unit via a parallel bus; a control unit which is connected to the data transfer control unit via a serial bus; and a local memory which is connected to the control unit via a parallel bus, wherein the control unit decides to assign, from a cache segment of either the cache memory or the local memory, a storage area which stores the data on the basis of a CPU operating rate and a path utilization of the parallel bus connected to the cache memory.